The objectives are to investigate several basic biochemical problems related to lipid metabolism and the physiological function of lipids. A number of related approaches will be used. The structure and function of the subunits of rat liver acetyl CoA carboxylase will be studied. The mechanism of the condensation reaction of fatty acid synthesis will be probed. The mechanism of action of insulin as it effects fatty acid synthesis in cultured animal cells will be further investigated. The regulation of the synthesis of unsaturated fatty acids will be studied in certain bacterial mutants. Changes in plasma membranes of muscle cells, that undergo fusion in cell culture, will be investigated. The relationship between lipid synthesis and cell growth will be studied in bacterial mutants that are temperature-sensitive in their ability to synthesize phospholipids.